1. Field of the Invention
The present invention relates to valve technology and more particularly, to a rotary switch type valve cap, which comprises two valve connectors that can be alternatively switched through a rotary motion.
2. Description of the Related Art
U.S. Pat. No. 5,960,815 discloses an air pump with an automatically switchable air valve cap that comprises a Presta (French) valve connector and a Schrader (American) valve connector arranged in parallel, and a switching device for switching the air flow direction. This design of valve cap has a large size. When attached to the tire of a conventional wire spoke wheel, the wire spokes will hinder the operation of the valve cap.
U.S. Pat. No. 8,402,987B2 discloses a dual-mode valve cap. This design of dual-mode valve cap has a small size. However, when connecting the dual-mode valve cap to the valve, the user needs to rotate the valve cap with the fingers to further thread an internal thread thereof onto an outer thread of the valve. This installation procedure is somewhat inconvenient.